Belt feeding means for guns



Jan. 14, 1936. D. M. WILLIAMS BELT FEEDING MEANS FOR GUNS 5 Sheets-Sheet 1 Filed March" 19, 1935 mm w .Jan. 14, 1936. D, w 2,027,893

BELT FEEDING MEANS FOR GUNS 5 Shets-Sheet 2 Filed March 19, 1935 3mm 2414 0 1. Q Q fl/ZJ L Jan. 14, 193 D. M. WILLIAMS BELT FEEDING MEANS FOR GUNS Filed March 19, 1955 5 Sheets-Sheet 3 H ZlwucMoo jal ici M. Wi'll z'alm 5% J fl JMZ L Jan. 14, 1936.

D. M. WILLIAMS BELT FEEDING MEANS FOR GUNS Filed March 19, 1935 5 Sheets-Sheet 4 Jan. 14, 1936.. D w 'AM 7 2,027,893

BELT FEEDING MEANS FOR GUNS Filed March 19, 1935 5 Sheets-Sheet 5 3mm fiarz'd' .44. Wzzlz'ama Patented Jan. 14, 1936 UNITED STATES PATENT OFFICE J I 28 Claims. The present invention relates to machine guns,

- and specifically to belt feeding mechanism-particularly adapted for feeding ammunition of small calibre and overall dimension. The term small calibre refe s to the diameter of the bullet. Some feature of the present invention may be embodied in belt feeding mechanism capable of feeding ammunition of large calibre,

One object of the present invention is to provide means for preventing the feed beltpawl from feeding more than one cartridge during its overtravel. c

Another object is to provide an extractor operating beneath the cartridges present in the ammunition belt, and extracting cartridges therefrom, said extractor also serving as a cartridge support.

A further object is to provide in place of the usual solid cartridge-receiving T slot, an expansible cartridge-receiving T slot means, said T slot 3 means functioning as guide jaws to receive and hold the base of extracted cartridges during the reciprocation ofthe bolt. v

Still another object is to provide a depressor feed cam functioning to insure that a cartridge' will be depressed in alignment with the barrel bore in event the gun mechanism fails to come to full open position due to firing a defective cartridge. This cam is positioned at the side of the receiver and preferably has a pair of forwardly,

and downwardly inclined cam surfaces spaced longitudinally of the receiver, at least one of said inclined cam surfaces being engaged by a spring pressed lug in accordance with the extent of the rearward movement of the bolt. This cam has means in advance of each cam surface to effect retraction of the lug.

In accordance with the present invention, the belt feed mechanismco'mprises a fixed guide, a slide mounted in said guide for reciprocating motion, a feed pawl pivoted to the slide and spring urged into engagement with the belt to feed the latter as the slide moves in-one direction, and

means to limit feeding engagement of the pawl with the belt to a distance of feeding movement.

ccrrespondingto the distance between successive cartridges. A cam may be fixed adjacent said guide on which the feed pawl travels and the cam may be arranged to permit feeding engagement cf the feed pawl with the belt to a distance equal to the distance between successive cartridges during the movement of the slide in belt feeding direction. This cam functions to hold the feed pawl out of feeding engagement with the belt by areciprocating bolt actuating member, the

former serving to extract cartridges from the belt. Means are provided actuated by the closing movement of the belt, to depress the belt at a point over the extractor and bring a cartridge into extracting relationship therewith, whereby initial movement of the bolt actuating member affects extraction of the engaged cartridge from the belt. The depressor, which is provided with a cam face, is pivoted to the bolt and positioned to overlie the belt upon the bolt being closed. The depressor cam face rides over the cartridge upon the final closing movement of the bolt and the cartridge is forced downwardly to bring the latter into engagement with the extractor.

The present invention also contemplates certain novel details of combination, construction and arrangement of parts of the improved machine gun, whereby certain important advantages are obtained as will be more fully described hereinafter, and pointed out in the claims, it being understood that thevinvention is susceptible to parting from the spirit of the invention.

The present invention will be disclosed and fully, explained by reference to the accompanying drawings, wherein:

Figure 1 is a longitudinal vertical section of a machine gun'in its closed or ready-to-fire position; I

Figure 2 is a longitudinalvertical section of the gun in its fully opened position;

Figure 3 is a transverse vertical section taken on line 3-3 of Fig. 1, showing the position the belt feed pawl, the holding pawl, and the ammunition extracting means take when the gun is in the closed position;

' Figure 4 is a similar view to Fig. 3, showing the position these parts take when the gun is in the opened position;

Figure 5 is a plan view showing the ammunition belt feeding mechanism.

Figure 6 is asideview of the expansible cartridge-receiving T-slot means, functioning as 0 Figure 7 is a horizontal, cross, sectional view taken on line of Fig. 6.

Figure 8 is a front end view of the bolt assembled with the expansible cartridge-receiving T-slot means.

Figure 9 is an inside end view of the right hand cartridge receiving T.

Figure 10 is a similar view of the left hand cartridge receiving T.

Figure 11 is an enlarged view of the cartridge extractor, shown in working relation with the powder case of a cartridge.

Figure 12 is a side view of the depressor feed cam.

Figure 13 is a bottom perspective of the same.

Figure 14 is a longitudinal sectional detail of a portion of the cartridge feeding means, and shows the belt feed pawl engaging the ammunition belt and cartridge.

The machine gun has the usual receiver or gun casing means In comprising side plates ll, bottom plate l2, top plate l3, back plate l4, trunnion block l5, jacket l6, and cover l1 pivoted on pin l8. I

The receiver is provided with the usual-trigger l9, pivoted at 20, said trigger cooperating with sear 2 I, the sear 2| operating under the influence of spring 22. As shown in Fig. 1, when the gun is in its ready-to-fire position. the sear 2i engages the notched portion of the striker 23, the latter being provided with striker points 24 and 25. The striker member 23 is brought into the ready-to-fire position by means of the cooking lever 26.

Located within the bolt 21 are many of the parts above referred to, said bolt 21 being provided with a rearward portion 28 and a forward portion 29, which engages the rearward portion of the movable chamber 30 which is secured in any suitable manner, for example, by threads 3| to the extension member 32, said extension member being provided with grooves, one on each side of the extension member to receive the bolt 21..

Secured to the left hand side plate of the receiver is a depressor feed cam 33 shown in detail in Figs. 12 and 13. The depressor cam is provided with a body portion 34 and a nose portion 35 having a lower face 36. The body portion is provided with a slot 31 having a forwardly and downwardly inclined cam wall or surface 38, and

a second rearwardly and downwardly inclined cam wall or surface 39/ In advance of the first cam surface 38, there is provided a bevelled surface 33a, and in advance of the second cam surface 39, there is provided a similarly bevelled surface 33b. A depressor 40 which is pivoted at 4| in the bolt 21, is provided with alug member 42 having mounted therein a depressor lug or plunger 43, which projects laterally of the depressor to engage one of the cam surfaces above mentioned, in accordance with the extent of the rearward movement of the bolt 21. The depressor lug 43 is held against the left hand side plate I I by means of a spring (not shown).

The lug 42 at its upper portion is provided with an upper cam surface 44 adapted on opening of the gun to engage the lower cam surface of the cover cam 45, as shown in Fig. 2, the cover cam serving to partially depress the depressor 40 on opening of the gun. The depressor lug 42 is provided at its lower portion with a lower cam portion 46 adapted to depress the cartridge 41, the dotted lines in Fig. 2 showing the cartridge 41 in its depressed position. v

Attached to the side receiver plate is a cam 48 having a caniming surface 49.

The cover spring 50 engages the upper portion of the depressor 40, said spring causing the lower cam surface ofv the depressor to engage'the cartridge 41 and push downwardly thereon, causing the shell head to engage the extracting edge 52 of the extractor 53, as shown in detail in Fig.

11, to thereby extract the cartridge from the ammunition belt.

The actuator or movable member 30 is provided with a powder case chamber 54 adapted to receive the powder case of a cartridge 58. Extend- 55 there is provided a gas contact face or pressure area 51.

The gaschamber 55 is provided with means for exhausting the ,gas present after the firing of a cartridge. v

Referring to Figs. 3, 4, and 5, the ,belt 59 containing a number of cartridges, including cartridges 41, 41a, 41b, and 410, is fed into the gun by means of the feed pawl 60, pivotally mounted at 6| on the slide 64, and provided with a projecting finger 62 serrated at 63. The feed pawl 60 is under tension of spring 65.

The slide 64 receives its reciprocating motion from the front end 66a of the feed lever 66, the latter being pivotally mounted at a point intermediate its ends in the cover plate l1, as for example, at the point 61. feed lever 66 is provided with a lug 68, operating in the slot 69, said slot running diagonally across the top of the bolt. As shown in Fig. 5, the slot runs from the right side front end of the bolt to the left side rear end of the bolt 21. The depressor lug 42 holds the cartridge 41 in working relation with the extractor 53.

The gun is provided with a feed block slot-'- ted to receive the extractor 53. The feed 'block 10 is not an integral part of the gun receiver, but is detachable so that it may be readily mounted and dismounted from the receiver. While the means for holding the block in the receiver is not shown, any suitable locating means may be used. Spring actuated and pivotally mounted on the left hand side of the feed block is a belt-holding pawl 1| having a serrated lug 12. The upper side of the feed block 10, preferably the left hand side, is provided with cam lug 13 having a face 14, said lug serving as a cam for raising the belt feed pawl 60 and preventing the latter from feeding more than one cartridge during one movement of the gun mechanism. This pawl is shown in Fig. 4 in its raised position riding on the cam Referring to Figs. 1, 6, '7, and 11, the cartridge 41 and the powder case 58 are shown in their relative working position when the gun is closed. The cartridge 41 and the powder case 58 are held by cartridge-holding T members and 16, pivotally mounted at 11 and 18 and actuated by spring 19. The T members 15 and 16 are provided, respectively, with hooks 80 and 8| for engaging the cartridge head 5|.

In the calibre .30 machine gun using the calibre .30 1906 Govt. ammunition, the head portion of the powder case projects a considerable extent from the calibre .30 cartridge chamber. This said projection is to the extent that the usual non-expansible T slot of fixed construction found on the usual calibre .30 machine gun bolts can engage the head of the cartridge. In calibre .30

The rear end of the- 1906 Govt. ammunition, the cartridge head is of solid head construction. Because this type of non-expansible solid T slot.

, members are used, this disadvantage is overcome. a 20 ly to a fully opened position carrying with it the v The solid Ts used with large calibre cartridges do not function well with small calibre cartridges, since the rims thereof do not afford sufficient gripping area. When the expansible-holding The operation of the gun is as follows:

The gun is s nown in its closed ready-to-fire position in Fig.1. The pull-on trigger It causes it to pivot on pin 20 and its forward end to pull sear 2| downwardly disengaging the sear with striker 23. The striker then moves forwardly under the influence of spring 23a causing the striker point to fire the cartridge. The gases escaping from the cartridge 58' will impinge against face 51 of the actuator 30 to thereby cause the actuator to have a powerful or violent rearward movement. As the actuator moves rearwardly, it carries extension 32, bolt 21 and their associated parts rearwardly. The depressor 49 acting under tension of spring 50 holds the head of cartridge 41, as shown in Figs. 1 and 11, in contact with the extractor 53. The extractor 53 being mounted on extension 32 and the depressor 49 pivoted at 4| on bolt 21, move as a unit rearwardly for a short distance. The actuator 30, the extractor 53 and the extension member 32 are shown at the end of said short movement in Fig. 2. During this rearward movement, the cartridge 41 is extracted from the belt 59, the latter being shown in Fig. 1, and in detail in Figs. 3

' and 4.

The actuator 39 healing come to rest, the bolt 21 and its associated parts continue to move rearwardly under the influence of the momentum gained through the movement of the actuator 30. The bolt mechanism continues moving rearwardlive cartridge 41. During this opening movement the depressor plunger 43, which is held against the left hand side plate I I by means of a spring,

=-.-has moved along the line D-D and has passed ,y over the several surfaces of depressor-cam 33 to the position shown in Fig.

When the bolt mechan1sm.1s at its closed,po.e

sition, as shown in Fig. 1, the belt feed mechanism is in the position shown in Fig. 3. The bolt 21 is provided with a slot 69, the slot running from the right hand front side of the bolt to the left hand rear side of the bolt.

It is tobe noted that the rear end of the feed lever 66 is provided with alug 68 operating in the slot 69, and that the slide 64 is provided with a slot 64a receiving the front end 65a of the feed lever 66. i

As the bolt 21 starts to move from its closed position rearwardly, the lever 66 moves counter clockwiseon its pivot61 by virtue of the construction above described, and then the forward end 66a of thegfeed lever begins to move the slide. 64 and the belt feed pawl 69 from the closed position shownin Fig. 3, to the left.

At the beginning of the rearward movement of the bolt and its associated parts, the extractor 53 begins to move rearwardly and. the extraction of cartridge 41 from the belt 59 has begun; As the bolt continues rearwardly to its fully opened position, the movement of the lever 56 continues and forces the slide 64 to continue its movement.

Upon continuation of this opening movement, the belt feed pawl 60 continues to the left under the influence of slide 64 and during this movement the belt feed pawl contacts with cam lug 13, and the belt feed pawl 60 and its finger62 is cammed upwardly to a position above the'cartridges and ammunition belt 59, and begins riding on face 13. A continuation of the rearward movement of the bolt to the fully opened position causes the slide 64 and belt feed pawl 60 and associated parts to assume the respective positions shown in Fig. 4. It will be noted that the movement to the left of the belt feed pawl has been to the extent that it would have engaged two cartridges at one movement rather than one,

if it were not cammed up to the disengaging position relative to the cartridges in the belt 59. The cam 13 provides means for preventing the feed-pawl 60 from feeding more than one cartridge at a time to the extractor 53, and compensates for the overtravel of the feed pawl 60.

While the above arrangement is particularly adapted for feeding small calibre ammunition,

such as calibre .22 rim fire cartridges, it may be used for feeding large calibre ammunition.

As the bolt continues its rearward movement, the cartridge 41 is extracted from the belt and is partially cammed downwardly by the action of the depressor lug 42 acting under the influence of the cover cam 45. When the gun is in its completely opened position, the cartridge 41 and the depressor 40 occupy the position as shown in Fig. 2.

During the closing movement of the bolt mechanism the depressor 40 and its plunger or lug 43 begins moving forwardly, the depressor plunger moving along line D-D until it contacts with cam face 39. Upon continuation of this movement the depressor plunger 43 travels forwardly and downwardly along the cam face 39 of the depressor feed cam 33, and depresses cartridge '41 to a position in alignment with the powder case chamber 54 of the actuator 39. This depressed position is indicated by dotted lines in Fig. 2.

The depressor plunger 43 now occupies the dotted position 431) in Fig. 12, and is under the positive-control of face 36, shown in Fig. 13. The further closing movement of the mechanism causes depressor plunger 43 to contact with cam face 43 of cam 4i! causing the depressor plunger to-raise the depressor to the position shown in Fig. 1. During this final closing movement, the cartridge 41 has been chambered in powder case 54 of actuator 39. Y

During the time the bolt mechanism is movingfrom the opened position as shown in Fig. 2, to the closed position, as shown in Fig. 1, the feed lever 66 acting under the influence of its lug 68 and operating in slot 69, is caused to rotate in an opposite direction to that occurring during the opening movement, that is, to rotate in a clockwise direction, thereby causing the front end 36a of the feed lever 65 to begin to move to the right' cupying the position occupied by cartridge 41b, and continuation of said movement causing the cartridge occupying the position indicated at 41b to occupy the position that the cartridge 41a occupies. This causes the cartridge that occupied the position at 41a to move over and engage extractor 53 and occupy the position of cartridge 41, as shown in Fig. 3. The gun is now in its closed position.

Referring again to the opening movement of the gun mechanism, it was indicated that the depressor 40 and the plunger or lug 43 will assume the position shown in Fig. 2, when the breech mechanism isin the full open position, and on the closing movement, the depressor plunger 43 will engage the cam face 39 of the feed cam 33. The aforesaid fully opened position of the gun mechanism is effected by a normal cartridge.

In the rearward movement of the bolt 21 under normal conditions, the spring pressed plunger 43 will ride over the cam 33, the latter being provided with a cam surface 33a in advance of the cam surface 38 and a second cam surface 33bwhich lies behind the cam surface 38, the cam surfaces 33a and 335 being smoothly beveled to retract the plunger, 43 during such rearward movement. i

In the event a defective cartridge is fired in the gun, it will cause the bolt mechanism to come to a partially opened position, and the depressor plunger 43 moving along the line D--D, will not come to the fully opened position but will stop on or about the position indicated at point 43a in Fig. '12, the plunger 43 riding upon the cam surface 33a and being protracted by the spring to drop into the pocket or groove 31 formed by the cam surface 33b and the cam surface 38, this partial opening movement of the gun represent ing the extreme opening movement of the gun' when a given defective cartridge is fired.

The bolt mechanism will now begin to travel forwardly causing the depressor plunger 43 to engage the cam face 38 to cam the plunger 43 downwardly to the normal position-indicated at point 43b in Fig. 12, as would be the case if the gun mechanism came to the .fully opened position, and the depressor plunger 43 engaged cam surface 39, this being the normal sequence of operation when the gun mechanism moves to the fully opened position under the action of a normal cartridge. The feed cam, above set forth, provides means for preventing malfunction of the gun when a defectivecartridge-is fired.

It is to be noted that when the gun mechanism is in the closed position and the cartridge 41 is in a position to be extracted by extractor 53, the vertical guide jaws and, 16, slotted to provide oppositely disposed hook members 80 and 8|, engage the rimmed head of the cartridge 41, the top portion of each hook member extending preferably above the cartridge head so that when the extractor has extracted the cartridge 41 from the belt 59 and said extractor reaches the limit of its rearward movement and ceases to extract or pull 'thecartridge 41 rearwardly of the hook members to move rearwardly, the depressor lug 42 forces cartridge 41 downwardly to a'pwtially depressed position.

The powder case 58 present in the actuator chamber 54 will be extracted during the opening '41 moves downwardly in the guide jaws it will strike the powder case 58, and eject the latter from the lower end of the guide members, and consequently from the gun.

It is to be observed that the ejection of the fired powder case will be effected whether or not the cartridge is defective because if a defective cartridge be fired and the bolt does not move to its normal rearmost position, the cam face 38 will be engaged by the plunger 43 and force the unfired cartridge down into alignment with the cartridge chamber, thereby ejecting the powder case of the defective cartridge from the lower ends of said guide members. i

It is to be noted that the present invention is particularly adapted for use in a machine gun operating by virtue of a relatively large gas contact or pressure area. One means of providing this pressure area has been set forth in the present application, and more fully in the application executed concurrently herewith and entitled 'Improvements in guns, and it is to be understood that as far as the basic principle of a large gas contact area is concerned, any of the arrangements set forth in the prior application, Serial No. 514,252, filed February 7, 1931, or in the case executed concurrently herewith, may be used in the present case, and the latter is therefore, a continuation-in-part of the prior application, Serial No. 514,252.

While the present invention has been described in connection with the gun illustrated in the drawings, it is recognized that it can be used in connection with all conventional types of machine guns, including those usually known under the terms gas operated machine guns and recoil operated machine guns". Such changes as are necessary are within the province of the ordinary worker skilled in the gun art. The present application and the specific arrangements therein disclosed may incorporate the principles set forth in the prior application.

In the claims the expression defective is intended to define a cartridge having potential sub-normal recoil.

I claim:

1. In a machine gun for using uniformly spaced belt carried cartridges, a belt feed including a fixed guide and a feedblock, a slide mounted in said guide for reciprocating motion, a feed pawl pivoted to said slide and spring urged into engagement with the belt to feed the latter as the slide moves in one direction, and a cam fixed on the feed block and on which said feed pawl travels, said cam being arranged to permit feeding engagement of the feed pawl with the belt for a distance equal to the distance between successive cartridges during movement of the slide in belt feeding direction and to hold the feed pawl out of feeding engagement with the belt during the remainder of the feeding movement of said pawl.

2. Ina machine gun for using uniformly spaced belt carried cartridges, a belt feed including a fixed guide and .a feed block, a slide mounted in said guide for reciprocating motion,

ing engagement of the feed pawl with the belt for a distance equal to the distance between successive cartridges during movement of the slide in belt feeding direction and to hold the feed pawl out of feeding engagement with the belt during the remainder of the feeding movement of said pawl, a reciprocating bolt movable between open and closed positions, and means operatively connecting said bolt and slide.

3. In a machine gun for using uniformly spaced belt carried cartridges, a belt feed including a fixed guide anda feed block, a slide mountedin said guide for reciprocating motion, a feed pawl pivoted to said slide and spring urged into engagement .with the belt to feed the latt'er'as the slide moves in one direction, and a cam fixed on said feed block and on which said feed pawl travels; said cam being arranged to permit feeding engagement of the feed pawl with the belt for a distance equal to the distance between successive cartridges during movement of the slide in belt feeding direction and to hold the feed pawl out of feeding engagement with the belt during the remainderof the feeding movement of said, pawl. a reciprocating bolt having a cam slot therein, a slide actuating lever pivoted intermediate its ends and having one end engaging said slide andits other end engaging in the cam slot of the bolt.

4. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by said'bolt actuating member to extract cartridges from the belt and normally spaced below the belt, and means actuated by closing movement of the bolt 'todepress the belt at a point over the extractor and bring a cartridge into extracting relation therewith whereby initial movement of the bolt actuating member effects extraction of the engaged cartridge from the belt. i

5.- ha machine gun, a receiver, means to feed a belt of cartridges'across said receiver, a bolt,

actuating member having limited reciprocating movement -in the receiver, a bolt reciprocable in the bolt actuating member, a 'cartridgeextractor carried by said bolt actuating member to extract cartridges fromthe belt and normally s'paced below the belt, a depressor pivoted to said bolt and positioned to overlie the belt upon the .bolt being closed and means to force the depressor and belt downwardly during the final part of the closing, movement of the bolt whereby to bring a cartridge into extracting relation to the extractor, v

6. In a machine gun, a receiver, means to feed a belt of cartridges across said ieceivena-bolt actuating member having limited reciprocating movement in the receiver, a'bolt reciprocable in the bolt actuating member, a cartridge extractor carried by. said bolt actuating member to extract cartridges from the belt and normally space'd below the belt, a depressor pivoted to said bolt and positioned to overlie the belt upon the bolt being said bolt to carry the extractor.

closed, said depressor having a cam face adapted cartridges from the belt and normally spaced be low the belt, means actuated by closing movement of the bolt to-depress the belt at a point over the extractor and bring a cartridge into extracting relation therewith whereby initial movement of the bolt actuating member efiects extraction of the engaged cartridge from the belt, and other means carried by said bolt engaging the base of the cartridge when engaged by the extractor, said last means moving with said bolt to carry the cartridge rearwardly from the extractor.

8. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by said bolt actuating member to extract cartridges from the belt and normally spaced below the belt, a depressor pivoted to said bolt and positioned to overlie the bolt upon the bolt being closed, means to force the depressor and belt. downwardly during the final part of the closing movement of the bolt whereby to bring a cartridge into extracting relation to the extractor, and other means carried by said bolt engaging the base of the cartridge when engaged by the extractor, said last means moving with said bolt to I carry the cartridge rearwardly from the extractor.

9. In a machine gun, a receiver, means to feed a belt of cartridges across said ,receiver, a b It actuating member having limited reciprocating movement in the receiver, a bolt reciprocable in the bolt actuating member, a cartridge extractor movement of the bolt, 9. spring inthe path of said depressor foi'cingthe depressor and belt downwardly to bring a cartridge into engagement with the extractor, and means carried by said bolt enadapted to ride 'over the. belt upon final closing gaging the base of the cartridge when engaged by the extractor, said last means moving with the cartridge rearwardly from 10. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement .in. the receiver and provided with a cartridge chamber, arbolt reciprocable in the bolt actuatingmember, a non-elevating cartridge support and extractor rigidly mounted directly under and supporting the rear end of the cartridge, a depressor separate from said cartridge support and extractor and pivoted to said bolt to engage a cartridge and depress the same against the cartridge support and extractor, cam means engaging" said depressor and effecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, and vertical bolt and positioning the depressor to ride over guides carried by the bolt to receive and hold the base of the extracted cartridge during reciprocation of the bolt.

11. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, means to extract cartridges from said belt, a depressor pivoted to said bolt to engage a cartridge and depress the same, cam means engaging said depressor and eifecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, a pair of opposed vertical guide jaws pivoted to the bolt about a vertical axis and slotted to engage the base of an extracted cartridge, and spring means urging said jaws toward each other.

12. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a

bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a non-elevating cartridge support and extractor rigidly mounted directly under and supporting the rear end of the cartridge, a depressor separate from said cartridge support and extractor and pivoted to said bolt to engage a cartridge and depress the same against the cartridge support and extractor, cam

means engaging said depressor and effecting parbolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chambena bolt reciprocable in the bolt actuating member, means to extract cartridges from said belt, a depressor pivoted to said bolt to engage a cartridge and deprws the same, cam means engaging said depressor and effecting partial depression during rearward movement or the bolt and completing the depression during a portion of the forward movement 01. said bolt, other cam means engaged by the depressor during the final part of the forward movement of the the belt and depress the same to bringa cartridge into engagement with the extracting means, a pair of opposed vertical guide jaws pivoted to the bolt about a vertical axis and slotted to engage the base of an extracted cartridge, and spring means urging said jaws toward each other.

14. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber,-a bolt reciprocable in the bolt actuating member, a non-elevating cartridge support and extractor rigidily mounted directly under and supporting the rear end of the cartridge, a depressor separate from said cartridge support and extractor and pivoted to said bolt to engage a cartridge and depress the same against the cartridge support and extractor, cam means engaging said depressor and efiecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, verticaLguides carried by the bolt to receive and hold the base of the extracted cartridge during reciprocation of the bolt, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and the further downward movement of the depressor effecting 'pushing of the fired'cartridge out of the lower ends of the guides.

15. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt -actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, means to extract cartridges from said belt, a depressor pivoted to said-bolt to engage a cartridge and depress the same, cam means engaging said depressor and effecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, a pair of opposed vertical guide jaws pivoted to the bolt about a vertical axis and slotted to engage the base of an extracted cartridge,

spring means urging said jaws toward each other,

the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to ,engage a fired cartridge and the further downward movement of the depressor effecting pushing oi the fired cartridge out of the lower ends of the guides.

16.'In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a non-elevating cartridge support and extractor rigidly mounted directly under and supporting the rear end of the cartridge, a depressor separate from said cartridge support and extractor and pivoted to said bolt to engage a cartridge and depress the same against the cartridge support and extractor,

cam means engaging said depressor and effecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, other cam means engaged by the depressor during the final part of the forward movement of the bolt and positioning the depressor to ride over the belt and depress the same to bring a cartridge into engagement with the extracting means, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and the further downward movement of the depressor effecting pushing of the fired cartridge out of the lower ends of the guides.

1'7. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a

bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, means to extract cartridges from said belt, a depressor pivoted to said bolt to engage a cartridge and depress the same, cam means engaging said depressor and effecting partial depression during rearward movement of the bolt and completing the depression during a portion of the forward movement of said bolt, other cam means engaged by the de ressor durin the final part of the forward movement of the bolt and positioning the depressor to ride over the belt and depress the same to bring a cartridge into engagement with the extracting means, a pair of opposed vertical, guide jaws pivoted to the bolt and slotted to engage the base of an extracted cartridge, spring means urging said jaws toward each other, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and the further downward movement of the depressor effecting pushing of the, fired cartridge out of the lower ends of the guides.

i 18. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver and, provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by the bolt actuating member and normally spaced below said belt, a depressor pivoted to said bolt to engage a cartridge and depress the same, a cam in said receiver engagedby the de-' pressor during its rearward movement to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudinally 'of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance. of each cam surface to effect retraction of the lug, and vertical guides 'carried by the bolt .to receive and hold the base of the extracted cartridge during re-' ciprocation of the bolt.

w 19. In a machine gun, a receiver means to feed a belt of cartridges across said receiver, a bolt actuating member having limited reciprocating' movement inthe receiver and provided with a cartr'idge'chamber, a bolt reciprocable -in the bolt actuating member, a cartridge extractor carried by the bolt actuating member and normally'spaced below said belt, a depressor pivoted to 'said bolt to engage a cartridge and depress the same, a cam in said receiver engaged by the depressor during its rearward movement to partially depress said depressor, a second cam at the side of. the receiver having a pair of for- 'wardly and downwardly inclined cam surfaces spaced longitudinally of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of. the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, a pair of-opposed vertical guide jaws pivoted to the bolt and slotted to engage the baseof an extracted cartridge, and spring means urging said jaws toward each other.

20. In a machine gun, a receiver, meansto feed a belt of cartridges across said receiver, a

bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried bythe bolt actuating member and normalspaced below said belt, a depressor pivoted tosaid belt to engage a cartridge'anddepress the same, a cam in said receiver engaged by the depi essor during its rearward movement to pardepressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudinally of the receiver, a spring pressedlug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent .of rearward movement of the bolt, said cam having means in advance of eachcam surface to effect retraction of the lug, other cam means engaged 'by the depressor during the final part of the forward movement ofthe bolt and positioning the depressor to ride over a cartridge in said belt and depress the cartridge into engagement with the extracting means.

21. In a machine gun, a receiver, means to feed a belt of cartridges acrosssaid receiver, a

spaced longitudinally of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent ofrearward' movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug,

a pair of opposed vertical guide jaws pivoted to the bolt and slotted to engage the base of an extracted cartridgefand spring means urging said'jaws toward each other, other cam means engaged by the depressor during the final part of the forward movement of the bolt. and positioning the depressor to ride over a cartridge in said belt and depress thecartridge into engagement with the extracting means.

-22. In a machine gun, a receiver, means to feed a belt of cartridges across said'receiver, a

bolt actuating .member having limited recipro eating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by thebolt actuating member and.

normally spaced below said belt, a depressor pivoted to said bolt to engage a cartridge and depress the same, a cam in said receiver engaged by the depressor during its rearward movement to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and, downwardly inclined cam surfaces spaced longitudinally of the receiver, a spring pressed lugprojecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, vertical guides carried by the bolt to receive and hold the base of the extracted cartridge dur-' ing reciprocation of the bolt, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and. the further downward movement of the depressor effecting pushing of the tired cartridge out of the lower ends of the guides.

-23. In a machine gun, a receiver, means to feed a belt of cartridges. across said receiver, a bolt actuating member having limited reciproeating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by the bolt actuating member and normally spaced below said belt, a depressor pivoted to said bolt to engage a cartridge and depress the same, a cam in said receiver engaged by the depressor during its rearward movement 'to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudinally of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, a pair of opposed vertical guide jaws pivoted to the bolt and slotted to engage the base of an extracted cartridge, spring means urging said jaws toward each other, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired ,to said bolt to engage a cartridge and depress the same, a cam in said receiver engaged by the depressor during its rearward movement to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudinally of the receiver/a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, other cam means-engaged by the depressor during the final part of the forward movement of the bolt and positioning the depressor to ride over the belt and depress the same to bring a cartridge into engagement with the extracting means, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and the further downward movement of the depressor effecting pushing of the fired cartridge out of the lower ends of the guides.

In a machine gun, a receiver, means to feed ahelt of cartridges across said receiver, a bolt actuating member having limited reciprocating movement in the receiver and provided with a cartridge chamber, a bolt reciprocable in the bolt actuating member, a cartridge extractor carried by the bolt actuating member and normally spaced below said belt, a depressor pivoted to said bolt to engage a cartridge and depressthe same, a cam in said receiver engaged by the depressor during its rearward movement to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudi-v nally of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of saidcam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, a pair of opposed vertical guide jaws pivoted to the bolt and slotted to engage the base of an extracted cartridge, and spring means urging said jaws toward each other, other cam means engaged by the depressor during the final part of the forward movement of the bolt and positioning the depressor to ride over the belt and depress the same to bring a cartridge into engagement with the extracting means, the downward movement of the depressor during rearward movement of the bolt being such as to bring an extracted cartridge in position to engage a fired cartridge and the further downward movement of the depressor afiecting pushing of the fired cartridge out of the lower ends of the guides. I

26. In a machine gun, a barrel having a cartridge chamber at its rear end, a bolt reciprocating longitudinally of the gun rearwardly of the cartridge chamber, a cartridge depressor, means carried by the bolt and gripping the rear end of a cartridge in said chamber to extract the same from the chamber after firing, and means for freeing a fired defective cartridge from the gripping means prior to the alignment of an unfired cartridge with said cartridge chamber, said means including means for depressing thedepressor to a fully depressed position upon forward movement of the bolt after partial rearward movement thereof.

27. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt actuating member having a reciprocating movement in the receiver, a cartridge chamber, a bolt in operative connection with the bolt actuating member, and a non-elevating cartridge support and extractor carried by the bolt actuating member, said cartridge support and extractor being rigidly mounted directly under and supporting the rear end of the cartridge belt, and means for feeding the extracted cartridge into said chamber.

28. In a machine gun, a receiver, means to feed a belt of cartridges across said receiver, a bolt' actuating member, a cartridge chamber, a re ciprocating bolt, cartridge extracting means, a

depressor pivoted to said bolt to engage a cartridge and depress the same, a cam in'said receiver engaged by the depressor during its rearward movement to partially depress said depressor, a second cam at the side of the receiver having a pair of forwardly and downwardly inclined cam surfaces spaced longitudinally of the receiver, a spring pressed lug projecting laterally of the depressor to engage one of said cam surfaces in accordance with the extent of rearward movement of the bolt, said cam having means in advance of each cam surface to effect retraction of the lug, and means for receiving and holding 

